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arXiv · 0704.3461

The vector-scalar mixing in nuclear medium and the two quark component of scalar meson from QCD sum rules

Su Houng Lee·Takumi Doi
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Abstract

We derive the QCD sum rules for the vector and scalar meson mixing in nuclear medium, using a two quark interpolating field for both mesons. Modeling the mixing via a nucleon hole contribution with known coupling constant, the sum rule can be used to determine the overlap of the interpolating field and the scalar meson. In the I=0 channel, we find a stable Borel curve and an overlap that is about 10% of the corresponding value in the pseudo scalar or vector channel. The sum rule in the I=1 channel is less reliable but also consistent with a small value for the overlap. These results suggest that both the $σ$ and $a_0$ have a small two quark and thus probably a large tetraquark components. We discuss the possibility of observing these scalar mesons from vector mesons emanating from the nuclear medium.

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Su Houng Lee, Takumi Doi. 2007-04-26. The vector-scalar mixing in nuclear medium and the two quark component of scalar meson from QCD sum rules. https://arxiv.org/abs/0704.3461

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